Legal is not the same as lawful.
If you cause harm to anyone.
If you cause loss to anyone.
If you defraud anyone in your contracts.
You have broken the law. Ignorance of the law is no excuse - it is simple to understand.
If you break the parliamentary statutes, you have offended against the legislation. The volume of legislation makes it impossible to know about or understand every bit of it. Ignorance of the legislation (not the law) is a natural state for everyone and we can be made to be criminals as soon as we leave our front door (or even before).
Our legal system has grown up to suit the needs of the legal profession. It is virtually impossible for anyone to understand, let alone navigate the legal system without being represented by a lawyer. A lawyer is an officer of the court and his first duty is to the court, not his client. Without the complications that the 'legal' system has have imposed by means of legislation, any man or woman can stand in front of a jury of their peers and defend themselves, or make a claim against someone who has wronged them, without the need of lawyers.